The September birthstone, Sapphire is chemically and structurally the same as Ruby - both are varieties of the mineral corundum Sapphires are well known among the general public as being blue, but can be nearly any color except shades of red or pink (since those are called rubies). Sapphire is also the Zodiac stone for the constellation of Taurus the Bull. It is associated with the values of truth, sincerity, commitment, and loyalty.
Oriented rutile crystal inclusions cause a six-pointed-star light effect (called asterism) to form the popular Star Sapphire.
Sapphires are well known from such places as Sri Lanka and India, and excellent specimens are also found in Tanzania and the Kola Pennensula of Russia. In addition, sapphires are found in many places throughout the world, including North Carolina, Brazil, and China.
Sapphires are extremely durable (only diamond and moisannite are harder). Artificial sapphire crystals are used are used as the crystal face in genuine Rolex watches, and they are extremely scratch resistant.